note 31431 deleted from function.define by spic

Constants CAN be redefined (kinda sorta) so watch out for this: <?php define ("CONSTANT", "Hello world."); echo CONSTANT; // outputs "Hello world." define ("CONSTANT", "My world.", true); echo CONSTANT; // outputs "Hello world." echo Constant; // outputs "My world." echo constant; // outputs "My world." ?> If a case-sensentive constant exists, redefining it as case-insensitive will produce no warning, all alternative case combinations will contain the new value and the original case spelling will contain the old. In a large complicated script, it may be best to check if a constant has already been defined and not rely on the rule that it can't be redefined.